The chromosomes of Papilio machaon have been studied by several researchers with different results: Federley (1938) reported n, 30, 31, 32, and 33 for Finnish forms, Lorkovic (1941) gave n, 30 for Yugoslavian forms, Maeki (1953) found n, 31 for Japanese forms, and Maeki & Ae (1966) informed n, 30 for Himalayan forms. The present author reexamined the chromosome of Papilio machaon hippocrates collected in the following localities, namely, Sapporo, Obihiro, Otaru, Hakodate, Goshogawara, Hirosaki, Tokyo, Nagoya, Nishinomiya, Fukuoka, Saga, and Kagoshima. Counts of chromosomes were made as to 616 nuclei in the primary spermatocytes based on the testes taken from 36 males. The chromosome number of these specimens showed a chromosomal polymorphism in the primary spermatocytes, ranging from n, 30 to n, 34, as shown in figs. 3-11 and table 1. The most frequent number of n, 31 was observed in 52.1% of the cells. The next most frequent chromosome number was n, 30, seen in 23.4% of the total. Also n, 32-nuclei occurred in 20%, n, 33-nuclei in 3.9%, n, 34-nuclei in 0.6% of the 616 nuclei observed. The basic number of Papilio inachaon hippocrates seems to be 30. The cause of the numerical variation lies in the presence of the supernumerary chromosome. The supernumeraries vary from 1 to 4 in number and are derived from the fragmentation of chromosomes through the course of the first meiosis.
